A method for using a composition for use as rock dust in an underground mine is disclosed. The composition includes a fine, wet ground inorganic particulate material treated with at least one hydrophobic treatment, and a coarse, untreated, dry ground inorganic particulate material. Also disclosed is a composition including coal dust and mine rock dust including a fine, wet ground inorganic particulate material treated with at least one hydrophobic treatment, and a coarse, untreated, dry ground inorganic particulate material. The amount of mine rock dust may be sufficient to render the coal dust explosively inert according to at least one of a 20-L explosibility test or an ASTM E1515 explosibility test. The fine, wet ground inorganic particulate material may be calcium carbonate. The coarse, untreated inorganic particulate material may be calcium carbonate. The fatty acid may be stearic acid.

A method for using a composition for use as rock dust in an underground mine is disclosed. The composition includes a fine, wet ground inorganic particulate material treated with at least one hydrophobic treatment, and a coarse, untreated, dry ground inorganic particulate material. Also disclosed is a composition including coal dust and mine rock dust including a fine, wet ground inorganic particulate material treated with at least one hydrophobic treatment, and a coarse, untreated, dry ground inorganic particulate material. The amount of mine rock dust may be sufficient to render the coal dust explosively inert according to at least one of a 20-L explosibility test or an ASTM E1515 explosibility test. The fine, wet ground inorganic particulate material may be calcium carbonate. The coarse, untreated inorganic particulate material may be calcium carbonate. The fatty acid may be stearic acid.

Mine dust in underground coal mines is potentially explosive and must be sampled and tested for sufficient inert content regularly. The present invention comprises a pneumatic mine dust sampling instrument equipped with a specially designed nozzle arrangement that delivers a controlled pulse of air which entrains the mine dust, similar to the entrainment process that happens during a mine explosion. The entrained mine dust can then be collected and tested for compliance with applicable federal standards.

Mine dust in underground coal mines is potentially explosive and must be sampled and tested for sufficient inert content regularly. The present invention comprises a pneumatic mine dust sampling instrument equipped with a specially designed nozzle arrangement that delivers a controlled pulse of air which entrains the mine dust, similar to the entrainment process that happens during a mine explosion. The entrained mine dust can then be collected and tested for compliance with applicable federal standards.

A method for using a composition for use as rock dust in an underground mine is disclosed. The composition includes a fine, wet ground inorganic particulate material treated with at least one hydrophobic treatment, and a coarse, untreated, dry ground inorganic particulate material. Also disclosed is a composition including coal dust and mine rock dust including a fine, wet ground inorganic particulate material treated with at least one hydrophobic treatment, and a coarse, untreated, dry ground inorganic particulate material. The amount of mine rock dust may be sufficient to render the coal dust explosively inert according to at least one of a 20-L explosibility test or an ASTM E1515 explosibility test. The fine, wet ground inorganic particulate material may be calcium carbonate. The coarse, untreated inorganic particulate material may be calcium carbonate. The fatty acid may be stearic acid.

A method for using a composition for use as rock dust in an underground mine is disclosed. The composition includes a fine, wet ground inorganic particulate material treated with at least one hydrophobic treatment, and a coarse, untreated, dry ground inorganic particulate material. Also disclosed is a composition including coal dust and mine rock dust including a fine, wet ground inorganic particulate material treated with at least one hydrophobic treatment, and a coarse, untreated, dry ground inorganic particulate material. The amount of mine rock dust may be sufficient to render the coal dust explosively inert according to at least one of a 20-L explosibility test or an ASTM E1515 explosibility test. The fine, wet ground inorganic particulate material may be calcium carbonate. The coarse, untreated inorganic particulate material may be calcium carbonate. The fatty acid may be stearic acid.

Mine dust in underground coal mines is potentially explosive and must be sampled and tested for sufficient inert content regularly. The present invention comprises a pneumatic mine dust sampling instrument equipped with a specially designed nozzle arrangement that delivers a controlled pulse of air which entrains the mine dust, similar to the entrainment process that happens during a mine explosion. The entrained mine dust can then be collected and tested for compliance with applicable federal standards.

The present disclosure provides a fire-prevention and extinguishing material for plugging an air leakage in an underground barrier pillar of a coal mine and a use method thereof. The fire-prevention and extinguishing material for plugging the air leakage includes an upper fabric layer, an intermediate layer, and a lower fabric layer. A plurality of fiber filaments are evenly distributed in the intermediate layer such that the intermediate layer has a flexible deformability. The intermediate layer is filled with a cement powder. The upper fabric layer is made of a flame-retardant flexible material. The upper fabric layer is configured to deform under a pressure to block off oxygen and plug the air leakage in the underground barrier pillar. The lower fabric layer is made of a water-soluble material.

The present disclosure provides a fire-prevention and extinguishing material for plugging an air leakage in an underground barrier pillar of a coal mine and a use method thereof. The fire-prevention and extinguishing material for plugging the air leakage includes an upper fabric layer, an intermediate layer, and a lower fabric layer. A plurality of fiber filaments are evenly distributed in the intermediate layer such that the intermediate layer has a flexible deformability. The intermediate layer is filled with a cement powder. The upper fabric layer is made of a flame-retardant flexible material. The upper fabric layer is configured to deform under a pressure to block off oxygen and plug the air leakage in the underground barrier pillar. The lower fabric layer is made of a water-soluble material.